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Avalia??o de genótipos de cafeeiros Arabica e Robusta no estado do Acre
Bergo, Celso Luis;Pereira, Rita de Cássia Alves;Sales, Francisco de;
Ciência e Agrotecnologia , 2008, DOI: 10.1590/S1413-70542008000100001
Abstract: this work aimed to introduce and evaluate 40 coffee genotypes of coffea arabica e coffea canephora species in soil and weather conditions of acre and had as main goal to provide cultivars to coffee producers with better potential of production. it was evaluated the genotypes icatu, bourbon, mundo novo, catuaí, obat? e catimor from coffea arabica species and genotypes conilon and robusta from coffea canephora species. the genotypes were originated from instituto agron?mico de campinas (iac) and embrapa rond?nia. the study was carried out in the experimental field of embrapa acre, rio branco, ac from 1995 to 2004 following a randomized block design, with 5 replicates. one studied characteristics such as yield, height, plant diameter and vigor. the best genotype of coffea arabica species, icatu group, showed to be the icatu-pr-182039-1(iac h 4782-7-788), which yielded 34 sacks/ha of clean coffee; right after came icatu iac-4041, icatu iac-2945, icatu iac-2944-mt, icatu iac- 4040 and icatu iac-4046 with mean yeld from 20 to 26 sacks. for catuai group, the best genotypes were obat? iac 4275, obat? iac 1169 e catimor iac 4466 with mean yield of 49, 45 e 37 sacks per hectare of clean coffee respectively. in the canephora species were evaluated eigth genotypes of conilon and robusta which did not show significant difference among them related to yield, although it was observed a difference of 7 sacks/ha more for the gentotypes iac 66-3 when compared to the local conilon. in this group it was noted drought stress during the dry season (july/august) for all the genotypes.
Adaptation to Long-Term Rainfall Variability for Robusta Coffee Cultivation in Brazilian Southeast  [PDF]
Lima Deleon Martins, Fernando Coelho Eugenio, Wagner Nunes Rodrigues, Sebasti?o Vinicius Batista Brinati, Tafarel Victor Colodetti, Bruno Fardim Christo, Dionicio Belisario Luis Olivas, Fábio Luiz Partelli, José Francisco Teixeira do Amaral, Marcelo Antonio Tomaz, José Domingos Cochicho Ramalho, Alexandre Rosa dos Santos
American Journal of Climate Change (AJCC) , 2018, DOI: 10.4236/ajcc.2018.74030
Abstract: Coffee is one of the world most traded agricultural commodities. Currently, a lot of attention has been on Robusta coffee (Coffea canephora Pierre ex A. Froehner) because it seems to evidence a greater tolerance to extreme climatic events than Arabica coffee (C. arabica L.). Despite this, only a few works have been developed aimed at discriminating the climatic vulnerability in regions which prioritize robust coffee production. The aim of this work was to analyze historical climatic variables in space and time for the characterization of climatic vulnerability of micro-regions, in search of mitigation and adaptation, which might support the improvement of production systems of C. canephora coffee trees. The case study was carried out for one of the largest production regions of Robusta coffee of the world, in Brazil, geographically located between the 39°38' and 41°50' West longitude meridians and the 17°52' and 21°19' South latitude parallels. The vulnerability was characterized by the spatial and temporal variation of rainfall and rainfall seasonal pattern (based on 30 years of historical data), elements of climatic water balance, elevation and area planted with Robusta coffee. The choice of mitigation and adaptation were based on widely validated criteria. Overall, the results show that the vulnerability of Robusta coffee is related to low index of rainfall, the rainfall seasonability and the water deficiency. In the studied region, there is approximately 42% of some type of water vulnerability during the year, with a severe to medium scale; this vulnerability is very pronounced in regions farther away from the coast of the Atlantic Ocean, since for a year approximately 92% of them are water deficient. In addition, the data show that this distance from the ocean implies a reduction of 75% in the phases of water surplus not only. The strategies of greater potential for adaptation and mitigation are related to the planting of improved genotypes, utilization of polycultures systems, increasing plant density, the implementation of irrigation systems and the management of spontaneous plants.
Antioxidant and Antiradical Activity of Coffee  [PDF]
Alexander Yashin,Yakov Yashin,Jing Yuan Wang,Boris Nemzer
Antioxidants , 2013, DOI: 10.3390/antiox2040230
Abstract: This review summarizes published information concerning the determination of antioxidant activity (AA) in coffee samples by various methods (ORAC, FRAP, TRAP, TEAC, etc.) in vitro and limited data of antiradical activity of coffee products in vitro and in vivo. Comparison is carried out of the AA of coffee Arabica and coffee Robusta roasted at different temperatures as well as by different roasting methods (microwave, convection, etc.). Data on the antiradical activity of coffee is provided. The antioxidant activity of coffee, tea, cocoa, and red wine is compared. At the end of this review, the total antioxidant content (TAC) of coffee samples from 21 coffee-producing countries as measured by an amperometric method is provided. The TAC of green and roasted coffee beans is also compared.
Recent Advances in the Genetic Transformation of Coffee  [PDF]
M. K. Mishra,A. Slater
Biotechnology Research International , 2012, DOI: 10.1155/2012/580857
Abstract: Coffee is one of the most important plantation crops, grown in about 80 countries across the world. The genus Coffea comprises approximately 100 species of which only two species, that is, Coffea arabica (commonly known as arabica coffee) and Coffea canephora (known as robusta coffee), are commercially cultivated. Genetic improvement of coffee through traditional breeding is slow due to the perennial nature of the plant. Genetic transformation has tremendous potential in developing improved coffee varieties with desired agronomic traits, which are otherwise difficult to achieve through traditional breeding. During the last twenty years, significant progress has been made in coffee biotechnology, particularly in the area of transgenic technology. This paper provides a detailed account of the advances made in the genetic transformation of coffee and their potential applications. 1. Introduction Coffee is one of the most important agricultural commodities, ranking second in international trade after crude oil. The total global production of green coffee is above 134.16 million bags (60?kg capacity) with a retail sales value in excess of $22.7 billion during 2010-11 in the world market [1]. Coffee is grown in about 10.2 million hectares land spanning over 80 countries in the tropical and subtropical regions of the world especially in Africa, Asia, and Latin America. The economics of many coffee growing countries depends heavily on the earnings from this crop. More than 100 million people in the coffee growing areas worldwide derive their income directly or indirectly from the produce of this crop. Coffee trees belong to the genus Coffea in the family Rubiaceae. The genus Coffea L. comprises more than 100 species [2], of which only two species, that is, C. arabica (arabica coffee) and C. canephora (robusta coffee), are commercially cultivated. Another coffee species, Coffea liberica is also cultivated in a small scale to satisfy local consumption. Almost all the coffee species are diploid ( 2 n = 2 x = 2 2 ) and generally self-incompatible except C. arabica which is a natural allotetraploid ( 2 n = 4 x = 4 4 ) self-fertile species [3]. In the consumer market, C. arabica is preferred for its beverage quality, aromatic characteristics, and low-caffeine content compared to robusta, which is characterized by a stronger bitterness, and higher-caffeine content. Arabica contributes towards 65% of global coffee production [4]. C. arabica is mainly native to the highlands of Southwestern Ethiopia with additional populations in South Sudan (Boma Plateau) and North
Microsatellite markers in analysis of resistance to coffee leaf miner in Arabica coffee
Pereira, Gabriella Santos;Padilha, Lilian;Pinho, Edila Vilela Resende Von;Teixeira, Rita de Kássia Siqueira;Carvalho, Carlos Henrique Siqueira de;Maluf, Mirian Peres;Carvalho, Bruna Line de;
Pesquisa Agropecuária Brasileira , 2011, DOI: 10.1590/S0100-204X2011001200010
Abstract: the objective of this work was to analyze coffee (coffea arabica) genotypes resistant to the coffee leaf miner (leucoptera coffeella) using microsatellite markers. sixty-six loci were evaluated, of which 63 were obtained from the brazilian coffee expressed sequence tag (est) database. these loci were amplified in bulks of individuals from f5 progenies of 'siriema' (c. arabica x c. racemosa) resistant and susceptible to the insect, in eight samples of c. racemosa, and in a f6 population of 'siriema' with 91 individuals segregating for resistance to the leaf miner. polymorphisms were verified for two simple sequence repeat (ssr) loci in bulks of the susceptible progenies. the two polymorphic alleles were present in around 70% of the susceptible genotypes in f5 and in approximately 90% of the susceptible individuals in f6. however, the polymorphic est-ssr markers among populations contrasting for resistance to leaf miner were not correlated to the evaluated characteristics. ssr markers show inter- and intraspecific polymorphism in c. arabica and c. racemosa.
Development of new genomic microsatellite markers from robusta coffee (Coffea canephora Pierre ex A. Froehner) showing broad cross-species transferability and utility in genetic studies
Prasad Hendre, Regur Phanindranath, V Annapurna, Albert Lalremruata, Ramesh K Aggarwal
BMC Plant Biology , 2008, DOI: 10.1186/1471-2229-8-51
Abstract: A small-insert partial genomic library of Coffea canephora, was probed for various SSR motifs following conventional approach of Southern hybridisation. Characterization of repeat positive clones revealed a very high abundance of DNRs (1/15 Kb) over TNRs (1/406 kb). The relative frequencies of different DNRs were found as AT >> AG > AC, whereas among TNRs, AGC was the most abundant repeat. The SSR positive sequences were used to design 58 primer pairs of which 44 pairs could be validated as single locus markers using a panel of arabica and robusta genotypes. The analysis revealed an average of 3.3 and 3.78 alleles and 0.49 and 0.62 PIC per marker for the tested arabicas and robustas, respectively. It also revealed a high cumulative PI over all the markers using both sib-based (10-6 and 10-12 for arabicas and robustas respectively) and unbiased corrected estimates (10-20 and 10-43 for arabicas and robustas respectively). The markers were tested for Hardy-Weinberg equilibrium, linkage dis-equilibrium, and were successfully used to ascertain generic diversity/affinities in the tested germplasm (cultivated as well as species). Nine markers could be mapped on robusta linkage map. Importantly, the markers showed ~92% transferability across related species/genera of coffee.The conventional approach of genomic library was successfully employed although with low efficiency to develop a set of 44 new genomic microsatellite markers of coffee. The characterization/validation of new markers demonstrated them to be highly informative, and useful for genetic studies namely, genetic diversity in coffee germplasm, individualization/bar-coding for germplasm protection, linkage mapping, taxonomic studies, and use as conserved orthologous sets across secondary genepool of coffee. Further, the relative frequency and distribution of different SSR motifs in coffee genome indicated coffee genome to be relatively poor in microsatellites compared to other plant species.Coffee tree, a member
Exploring drought tolerance in coffee: a physiological approach with some insights for plant breeding
DaMatta, Fábio Murilo;
Brazilian Journal of Plant Physiology , 2004, DOI: 10.1590/S1677-04202004000100001
Abstract: this paper briefly reviews some selected traits (leaf area, crown architecture, water-use efficiency and carbon isotope discrimination, water relations and root characteristics), which may be explored in breeding programmes to tolerance to drought stress in arabica and robusta coffee.
Exploring drought tolerance in coffee: a physiological approach with some insights for plant breeding  [cached]
DaMatta Fábio Murilo
Brazilian Journal of Plant Physiology , 2004,
Abstract: This paper briefly reviews some selected traits (leaf area, crown architecture, water-use efficiency and carbon isotope discrimination, water relations and root characteristics), which may be explored in breeding programmes to tolerance to drought stress in arabica and robusta coffee.
Equine poisoning by coffee husk (Coffea arabica L.)
Diego Jose Z Delfiol, Jose P Oliveira-Filho, Fernanda L Casalecchi, Thatiane Kievitsbosch, Carlos A Hussni, Franklin Riet-Correa, Jo?o P Araujo-Jr, Alexandre S Borges
BMC Veterinary Research , 2012, DOI: 10.1186/1746-6148-8-4
Abstract: Six horses fed coast cross hay ad libitum were given access to coffee husks and excitability, restlessness, involuntary muscle tremors, chewing movements and constant tremors of the lips and tongue, excessive sweating and increased respiration and heart rates were the most evident clinical signs. Caffeine levels were measured in the plasma and urine of these horses on two occasions: immediately before the coffee husks were made available to the animals (T0) and at the time of the clinical presentation of intoxication, 56 h after the animals started to consume the husks (T56). The concentrations of caffeine in the plasma (p < 0.001) and urine (p < 0.001) of these animals were significantly greater at T56 than at T0.It was concluded that consumption of coffee husks was toxic to horses due to the high levels of caffeine present in their composition. Therefore, coffee husks pose a risk when used as bedding or as feed for horses.Brazil is the largest coffee producer in the world, and coffee grain processing generates a large amount of waste, given that close to 60% of the crude weight of the bean corresponds to the husk. The coffee (Coffea arabica) husk is rich in organic compounds and contains substances such as tannins, polyphenols and caffeine; the latter is often found in higher concentrations in the husk than in the bean [1]. Several studies have addressed reuse of the husks, especially as organic fertilizers, in tea production, caffeine extraction and the feeding of ruminants and pigs [2-6].Caffeine (C8H10N4O2) is a methylxanthine, which the most important effect is adenosine receptor antagonism [7]. Adenosine reduces spontaneous neuronal firing in multiple brain areas, and its presynaptic action inhibits neuronal release of acetylcholine, norepinephrine, dopamine, serotonin and gamma-aminobutyric acid; it produces sedation and has an anticonvulsant effect [8]. When caffeine binds to adenosine receptors, it prevents the inhibitory effects of adenosine [8], thereby
The Effects of Shade Tree Types on Light Variation and Robusta Coffee Production in Vietnam  [PDF]
Nguyen Van Long, Nguyen Quang Ngoc, Nguyen Ngoc Dung, Paul Kristiansen, Isa Yunusa, Chris Fyfe
Engineering (ENG) , 2015, DOI: 10.4236/eng.2015.711065
Abstract: Vietnam is well-known as the second largest global coffee producer and the largest worldwide exporter of Robusta coffee. However, the Robusta coffee sector in Vietnam is facing many problems, including low quality, high external inputs and water shortages as a result of shade tree eradication. A six-month research project was conducted that focused on effects of shaded tree types on variation of light intensity and aspects of Robusta production. Three shade tree species at different planting densities and shade provision were investigated, including 46 trees of Durian ha–1 (14% shade), 35 trees of Sennaha–1 (17% shade), and 60 trees of Leucaena ha–1 (34% shade), and unshaded site (Open) was used as a control. The study found that light intensity declined 50% with Durian, 58% with Senna and 60% with Leucaena compared with the Open site (2096 μmol?m–2?s–1). Within the coffee canopy, a significant decline in light intensity was observed from the top of the canopy to the bottom. The percentage of light at the middle (90 cm above ground) and bottom (30cm) levels of the coffee canopy was declined by 81% and 88% respectively for the Open site, and 86% and 92% for the Leucaena site. There were no differences in the number of flowers branch–1 tree–1 and fruit set between shaded and unshaded coffee sites. However, a significant difference in first fruit drop was observed.
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